Correlating the abdominal drawing in manoeuvre between ultrasound imaging, pressure biofeedback and manual palpation measurements in participants with low back pain: an observational cross-sectional study

Abstract

Background: Physiotherapists have several options to measure lateral abdominal muscle (LAM) activity clinically, including ultrasound imaging (USI), pressure biofeedback units (PBU) and manual palpation scales. However, the concurrent validity of these tools is yet to be examined. Understanding how these tools correlate will help physiotherapists make informed choices about tool selection. Objectives: To determine the correlation between the prone PBU test, manual palpation and USI measures (preferential activation, preferential activation modified and transversus abdominis muscle ratios and transversus abdominis slide) for examining the ADIM. Design: Observational cross-sectional study. Method: 58 participants with LBP underwent measurement of LAM activation using the three measurement tools across two sessions (7-14 days apart). Results were analysed using correlation coefficients and tested for statistical significance. Results/findings: Reliability of activation measures ranged from moderate to good. Correlations were found between manual palpation, PBU and USI, however, were non-significant after a Holm-Bonferroni correction. Conclusions: The findings question the concurrent validity of these tools, suggesting one cannot be used in place of another for measuring LAM activation during the ADIM